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The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.
Thought I would share a successful repair. Below is text from my brother who worked on my Honda 9.9 outboard:
My brothers motor had an odd habit of shutting down when at idle after 1min 17seconds. It would always promptly restart, run great, perform at speed, but as soon as it was returned to idle...it would die 1:17 over and over again. We had cleaned carb several times attempting to correct the problem without success. When idling it never sputtered, coughed or hiccupped..it would just shut down quick and clean. I began to think it was an electrical issue. We attempted a fix last fall when doing a general service and were gonna replace the impeller ...but due to long delivery times and an impending trip down the Tennessee River...it was put off. Besides...the telltale stream was fine..maybe not as strong as other Hondas..but present. This Saturday, it became worse...coughing and sputtering at high idle (but still ran great at high rpm)...I received a call for assistance. When I arrived at the lake some 30+ minutes later...I pulled the carb..but was shocked by how hot the motor and carb were...I assumed it was vapor locking with the fuel being extremely hot. We pulled the motor and I brought it home. I removed the lower unit and found the impeller in bad shape. New impeller installed today...no carb work, and the motor runs beautiful...over 30 minutes of idle time in gear and not one hiccup interesting lesson...that a weak coolant water flow can cause the engine to overheat at idle and cause the high temp switch to cause a shut down..but run fine at full throttle.
Added note: it appears that the impeller had shed one blade quite awhile ago based on how worn down the remnant was. A second blade was about to separate, probably causing the problem that resulted in a call to action.
Thanks for sharing your story. I will probably get my bottom painted some time this summer and if that happens, wanted to do some outboard maintenance including changing out the impeller.
Dave Bristle Association "Port Captain" for Mystic/Stonington CT PO of 1985 C-25 SR/FK #5032 Passage, USCG "sixpack" (expired), Now on Eastern 27 $+!nkp*+ Sarge
I don't know exactly. I believe it was last changed as a preventive measure prior to my trip down the Mississippi River, which was in the fall of 2017.
I just read an article about “regular” gas formulation for summer 2022: it’s E15! Somehow, somewhere along the line the gasoline wholesalers decided unilaterally that they’d begin selling E-15 as “regular” auto fuel. Now I realize that boat gas is usually very marked up (25-30% over “street” prices) so many folks, including me, will fill their boat fuel tanks at the local fillin’ station rather than at the fuel dock. DON’T! Unless you know for a fact that it’s E-10 gas. Not only will it wreck your outboard engine fuel system (hoses, carb, injectors) but it will make your engine run a lot hotter than E-10.
Had the same problem with my 9.9 with dying at idle. Did the carb thing, plugs, etc.. Turning out it was the little o-ring in the gas tank connection. Would let enough air in at idle but would overcome it at higher speeds. Now I change it out every spring.
Dale Veldhuizen 1984 C25 SK/SR #4389 MtnCat Lake Granby in Rocky Mtn Nat Park
That O ring has caused me plenty of headaches in the past. On the Honda it’s tucked inside the fuel line fuel connector, rather than on the engine side. Normally I’ll just order a new connector or wrap the pin with yellow Teflon tape.
Wow! Kav, I had not heard that, thanks for the info. Meanwhile, my gas dock is selling 89 octane gas with 10% ethanol (I asked) at $6.49 per gallon. I’m super glad that I only use 3.5 gallons at a time. A whopping $25. The stinkpotters are buying 100-200 gallons at $6 for gas or $10 for diesel. That’s why most of them are enjoying time at the docks, or teaming up with other boaters to go out for a short cruise altogether on one boat.
The fuel connector from fuel line to the engine, many years ago I had issues that turned out not to be the oring but a mini stress crack in the plastic connector adjacent to the oring. Changing out the plastic fuel connector resolved the issue.
I went sailing today and as I returned/entered the Marina, my outboard dies. Tried starting it numerous times and pumping the rubber bulb since it was not holding much pressure. Luckily, the "B" dock which the boat was drifting toward had no boats alongside and so I pulled alongside with my hook and tied up using the furling line and the main sheet line. I noticed the issue right away, the fuel connector was not fitting snug and clicked into the outboard. This probably happened when I was approaching the marina and lowered the outboard - The fuel hose stretched a bit since the rubber bulb got snagged on the cushion corner. I had freed the bulb when this occurred but did not notice that the fuel connector backed out about 1/8" until I pulled along B Dock. 2 second fix - clicked the fuel connector into the outboard and outboard started fine - then made my way to my slip on C Dock. Once in my slip. I looked over the connector and did a little bending action on the metal clip so that clicking the connector into place would be a bit more secure.
Having solved this issue quickly, no mishaps to my boat approaching the other dock, I was feeling pretty good about myself...until I was putting gear away and bumped my head on the cabin bulkhead. That put my ego back in check!
Notice: The advice given on this site is based upon individual or quoted experience, yours may differ. The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.